Charcot Marie Tooth disease (CMT) is the eponym for heritable peripheral neuropathy. These are among the most common inherited neuromuscular diseases, affecting approximately 1 in 2500 people. Mutations in more than 30 genes cause CMT, and loci for more than 40 additional genes have been identified. CMT is separable into three specific groups: (1) CMT1, dominantly inherited demyelinating neuropathies; (2) CMT2, dominantly inherited axonal neuropathies; and (3) CMT4, recessively inherited neuropathies. Genetically authentic animal models exist for many forms of CMT, and have provided the data compelling the clinical trials in humans that are currently underway for CMT1 A. Despite these advances, no effective therapies are available for any form of CMT, natural history data are available for only the most common types (CMT1A and CMT1X), and many potential genotype-phenotype correlations remain unknown. To address these issues, we have created the Hereditary Neuropathy Consortium (HNC), a collection of clinical researchers with demonstrated expertise in CMT. Sites within the HNC include Wayne State University, the National Hospital for Neurology/Neurosurgery in London, the University of Rochester/Muscle Study Group (MSG), the University of Pennsylvania/Children's Hospital of Philadelphia (CHOP), and the University of Miami, Florida. Two Pilot Projects will be performed. Dr. Gyula Acsadi from WSU will develop a Pediatric Scoring System for CMT patients, aided by Dr. Muntoni from London and Dr. Finkel from CHOP. Dr. Scherer will develop a Website patterned after OMIM for patients and researchers interested in CMT. Two Clinical Research Projects will be performed. Dr. Shy, from WSU, will undertake a natural history analysis of CMT1B, CMT2A, and CMT4A. Drs Zuchner and Vance, from Miami, will perform a search for modifier genes in various forms of CMT. Dr. Mary Reilly from London will lead a training program for postdoctoral fellows and junior faculty members that will involve all sites including the MSG. Dr. McDermott, from Rochester, will be the HNC Biostatistician. The Charcot Marie Tooth Association (CMTA), CMT United Kingdom (CMTUK) and TREAT-NMD organizations will interact extensively with the HNC.